Polymers For Surface Modification Research Articles

カテコール系高分子を用いる材料表面改質と色材への応用

カテコール系高分子を用いる材料表面改質と色材への応用

Effect of the composition of the copolymer of carboxybetaine and n-butylmethacrylate on low-fouling property of dynamically formed membrane

The effect of the composition of the copolymer of 1-carboxy-N,N-dimethyl-N-(2-methacryloyloxyethyl) methanaminium inner salt (CMB) and n-butylmethacrylate (BMA) (poly(CMB-co-BMA)) as a surface modification polymer on the low-fouling properties of dynamically formed membranes was systematically investigated, and the optimum composition for this method was found to be 35:65 [mol:mol], which was prepared from the monomer solution containing 50:50 [mol:mol] of CMB:BMA in the feed (CMB50). This optimized dynamically formed membrane exhibited excellent low-fouling property against both hydrophilic protein and hydrophobic protein. To discuss the reason for this low-fouling property, the hydration states of the polyCMB–water and CMB50–water systems were measured using DSC. The results showed that the water structure in the polyCMB–water system is very similar to that in the poly(2-methacryloyloxyethyl phosphorylcholine) (polyMPC)–water system, which is one of the best-known zwitterionic polymers used for biomaterials, and that the water structure in the CMB50–water system has much in common with that in the polyCMB–water system. These water structures are one of the reasons for this system’s low-fouling properties.

High-fluence implantation of negative metal ions into polymers for surface modification and nanoparticle formation

Negative ion implantation has been applied to polymers in order to modify the surface and to fabricate nanoparticles. Metal nanoparticles in the vicinity of a polymeric surface are promising for biomedical applications as well as nonlinear optical applications. Substrates of polymethyl methacrylate (PMMA) were implanted with Ag − and Cu − of 60 keV at 3 μA/cm 2 up to 3×10 17 ions/cm 2. Optical absorption spectra of the implanted PMMA were measured in a photon range from 0.5 to 4.5 eV. A peak of surface plasmon resonance (SPR) emerges in the absorption spectra above about 1×10 17 ions/cm 2, both for the Ag − and Cu − cases. A coexisting absorption slope, due mostly to defects, increases but tends to saturate with ion fluence. The SPR peak of Ag-implanted PMMA is much broader than that of the Cu-implanted one. Corresponding to the SPR spectra, metal nanoparticles are observed by cross-sectional TEM. With increasing ion fluence, the Ag nanoparticles spread out towards the surface, in contrast to the localized Cu nanoparticles. The results demonstrate that metal nanoparticle fabrication in polymers is capable by using appropriate low-energy ions and provides a variety of spatial distributions dependent on ion species and fluence. In particular, Ag − ion implantation fabricates surface-exposed/gradient nanoparticles, which are suitable for biomedical applications such as anti-microbial effects.

New acrylic polymers for surface modification of enzymes of therapeutic interest and for enzyme immobilization.

New acrylic polymers for surface modification of enzymes of therapeutic interest and for enzyme immobilization.